BOGOTA, Jan 19 (Reuters) - The largest union at Cerrejon, Colombia’s top thermal coal mine, was set to meet with the company on Friday to hear a new salary and benefits offer before deciding whether to hold a vote on a possible strike.

A work stoppage at the Cerrejon mine, which belongs in equal parts to BHP Billiton, Anglo American and Glencore and produces about 37 percent of Colombia’s total output, could reduce production and overseas sales from the world’s fifth-largest coal exporting nation. Production and exports at Cerrejon, which produced 31.7 million tonnes of coal in 2017, fell for a third straight year as heavy rainfall affected operations, the mine’s owners said this month.

“We will meet with the company this afternoon after a request from them to present a new offer, the fourth in this negotiation,” Aldo Amaya, president of the Sintracarbon union, told Reuters on Friday.

“We will listen to the offer, but we’re far off,” he said. The company most recently offered a salary increase of 5.55 percent for this year, Amaya said, while the union has demanded 12 percent.

The company, which has 5,000 workers, did not immediately respond to a request for comment from Reuters.

If there is no deal Friday, the union has 10 days to call a vote among its 4,800 members on whether to strike or take the matter to arbitration. A walkout could begin within three days of a vote.

The last strike at Cerrejon, which produces coal at its open pit mine in Colombia’s northern La Guajira province, was in February 2013 and lasted 32 days.

Cerrejon, one of the world’s largest open-pit coal mines, has a railway line spanning more than 90 miles (150-km) and a seaport to handle shipments. (Reporting by Luis Jaime Acosta; Writing by Julia Symmes Cobb; Editing by Tom Brown)